PEQ: Graph should reflect Q value for shelf filters

harkpabst

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The PEQ feature in WiiM's products has developed very well over time and definitely turned into an extremely powerful tool. One great feature is the support of fully flexible filter Q values, not only for peak filters, but also for high shelf and low shelf filters.

Unfortunately, the effects of different Q values are currently displayed for peak filters, only.

For example, here are the graphs for a 200 Hz +10 dB PK filter with either Q=1.5 or Q=0.15. The difference is obvious and understood very intuitively.

PK Q 1.5 current.jpg
PK Q 0.15 current.jpg


In contrast, the graphs for a 200 Hz +10 dB LS filter currently look exactly the same for Q=1.5 and Q=0.15. But this is not what really happens.

LS Q 1.5 current.jpg
LS Q 0.15 current.jpg


My request is to visually display the effect of different Q values for shelving filters as well.

For the LS filters shown above this should look somewhat like this:

LS Q 1.5 request.jpg
LS Q 0.15 request.jpg

Although I am well aware of the fact that precise measurements should ideally be combined with listening experience, this would be a more than welcome improvement.

Please upvote if you agree, please comment if you don't.
 

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  • LS Q 1.5 current.jpg
    LS Q 1.5 current.jpg
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  • LS Q 0.15 current.jpg
    LS Q 0.15 current.jpg
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  • LS Q 1.5 request.jpg
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  • LS Q 0.15 request.jpg
    LS Q 0.15 request.jpg
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The PEQ feature in WiiM's products has developed very well over time and definitely turned into an extremely powerful tool. One great feature is the support of fully flexible filter Q values, not only for peak filters, but also for high shelf and low shelf filters.

Unfortunately, the effects of different Q values are currently displayed for peak filters, only.

For example, here are the graphs for a 200 Hz +10 dB PK filter with either Q=1.5 or Q=0.15. The difference is obvious and understood very intuitively.

View attachment 7290
View attachment 7291


In contrast, the graphs for a 200 Hz +10 dB LS filter currently look exactly the same for Q=1.5 and Q=0.15. But this is not what really happens.

View attachment 7296
View attachment 7297


My request is to visually display the effect of different Q values for shelving filters as well.

For the LS filters shown above this should look somewhat like this:

View attachment 7298
View attachment 7299

Although I am well aware of the fact that precise measurements should ideally be combined with listening experience, this would be a more than welcome improvement.

Please upvote if you agree, please comment if you don't.
I couldn't agree more.
That was exactly the discomfort I was feeling today while playing with the PEQ LS.

Thanks for the heads up.🤗
 
Is the Q factor maybe fix for shelf filters?
As you can see from the screenshots it can be configured in the WiiM Home App.

Also measurements performed by @Wiimer (when trying to simulate the still missing low pass and high pass filters using shelf filters) did clearly show the expected overshoot when increasing the Q value. In his case this was highly undesirable.


I think we know for sure that the Q factor is not fixed.
 
As you can see from the screenshots it can be configured in the WiiM Home App.

Also measurements performed by @Wiimer (when trying to simulate the still missing low pass and high pass filters using shelf filters) did clearly show the expected overshoot when increasing the Q value. In his case this was highly undesirable.


I think we know for sure that the Q factor is not fixed.
Agree , they should fix the display and show the overshoot with different Q values.
However , a variable Q using shelving filtering with overshoot is a very useful tool , so it shouldnt be limited to higher values than Q=1.

As it is, the possibility to use higher Q values with shelving is one of the best things with the WiiM streamers. To get better bass, for example:

 
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Agree , they should fix the display and show the overshoot with different Q values.
However , a variable Q using shelving filtering with overshoot is a very useful tool , so it shouldnt be limited to higher values than Q=1.
I explicitly do not request to introduce a fixed Q of 0,707 or whatever value (even if that would ensure that display and reality match up). I want to keep variable Q shelving filters, just please fix the display, WiiM.
 
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